Apparatus for drying coating paper



March 13, 1934. c. c. WILLIS APPARATUS FOR DRYING COATING PAPER FiledNov. 29, 1930 2 She'ets-Sheet 1 INVENTOR Cfiar/es C. 14/17/115 BY ATTQ RN EY EM 2% Mm March 13, 1934. c. c. WILLIS APPARATUS FOR DRYING COATINGPAPER Filed Nov. 29, 1930 2 Sheets-Sheet 2 Q U i; I? ::gg gw 5 5 i 0 E:E 2. 125 1. :35; ,e woxwbh 1M1 m m o INVENTOR C. AY/12s BY ATTORNEYChum? ZMIZW Patented Mar. 13, 1934 UNITED STATES PATENT OFFICE APPARATUSFOR DRYING COATING PAPER Application November 29, 1930, Serial No.498,981

1 Claim.

This invention relates to methods and apparatus for coating paper, andrelates more particularly to the drying of paper after being coated.

An object of the invention is to provide drying apparatus for coatingpaper which prevents counter-curl of the paper.

Another object of the invention is to provide apparatus for dryingcoated paper which leaves the paper free to contract and expand.

Another object of the invention is to provide apparatus for dryingcoated paper which allows the paper during the drying operation toassume its free, natural state and to avoid wrinkles.

5 Other objects and advantages of the invention will be apparent fromthe description set out below when taken in connection with theaccompanying drawings.

The invention will now be described with reference to the drawings, ofwhich:

Fig. 1 is a diagrammatic view of a paper coating apparatus utilizing thepresent invention;

Fig. 2 is an enlarged view of a portion of the drying chamber of Fig. 1;

Fig. 3 is a sectional view along the lines 3-3 of Fig. 2, looking in thedirection of the arrows, and

Fig. 4 is a projected view of a portion of the conveyer and shows theprojection of the drying 0 air against the paper.

Fig. 5 is a projected view illustrating the connection of the crossmembers to the chain links.

The complete plant shown by Fig. 1 comprises the roll of paper 5 to becoated, the ordinary tensioning rollers, the coating roller 6, whichapplies color from the bath '7 to the paper, and the smoothing rolls 8,which are used to smooth the coating applied to the paper. The coatedpaper, after leaving the smoothing rolls, passes 40 onto the upper sideof the conveyer 9, just beyond the conveyer roller 10, and is caused todrape loosely between adjacent pairs of the conveyer cross members 11.The paper is subjected to a strong downwardly directed stream of air,

from the air duct 12, to cause the paper to remain partially loopedbetween the adjacent pairs of the cross members of the conveyer. Thepaper next passes on the conveyer under the air duct 13, which, like theair duct 12, directs a strong stream of air downwardly on the paper tokeep it partially looped between the cross members. The conveyer 9reverses its direction at the roller 14, so that the paper lies on theunder side of the conveyer, after passing the roller 14. To prevent thepaper from leaving the under side of the conveyer through the force ofgravity, and also to keep the paper in its partially looped positionbetween the cross members, a strong stream of air is directed from theair duct 15 against the under side of the paper (which was formerly theupper side), to force the paper against the cross members, and to keepthe paper in tension. The conveyer again reverses the direction of thepaper at the roller 16, and while being carried around by the conveyer,is forced against the cross members of the conveyer by air streams fromthe end 17, of the air duct 15. After changing its direction, due to thereversal of the conveyer so that what was formerly the lower surface isnow the upper surface of the paper, the air streams from the air duct 18are directed against the upper surface of the paper to maintain thepaper in its partially looped position between the cross members of theconveyer. The conveyer again reverses the direction at the roller 19 andair streams are directed upward against the paper from the air duct.20to insure that the paper remains in its partially looped positionbetween the cross members on the lower side of the conveyer. The paperthen leaves the conveyer at the roller 21 and passes over the auto guiderollers 22, the pulling drums 23, and is rewoundat the double centerrewinder 24.

Figs. 2 and 4 show clearly the arrangement of the paper in its partiallylooped position over the cross members 11 of the conveyer 9.

Fig. 2 is an enlarged view of a portion of the central section of theconveyer shown by Fig. l and shows the air from the air ducts 15 and 16projected against and maintaining the paper on theunder side of theconveyer as it passes from the under side to the upper side of theconveyer 9. The air ducts 15 and 16 are provided with spaced apertures25 across and along 95 the path of the conveyer 9 through which the airis projected against the surface of the paper.

These spaced apertures are shown more clearly by Fig. 4 which is aprojected enlarged view of the upper side of the conveyer 9 shown byFig. 2. Both Figs. 2 and 4 illustrate clearly how the paper is retainedpartially looped against the under side of the conveyer 9 as it passesthrough the drying chamber.

Fig. 2 illustrates how the paper is maintained against the inner surfaceof the conveyer 9 as the conveyer is carried around by the roller 16.After passing the roller 16, the paper lies on the upper side of theconveyer 9 and is subjected to the pressure of air directed downwardlyfrom the air duct 16 to maintain it in its partially looped positionbetween the cross members 11 of the conveyer.

The air is forced into the air duets 12, 13, 15, 18 and 20 under highpressure from any suitable source (not shown) and serves eiTectively todry the coated paper as it passes along the conveyer. Due to the factthat the paper is partially looped between the cross members of theconveyer, as shown more clearly by Figs. 2, 3 and 4, more surface of thepaper is exposed to the drying action of the air, and furthermore, sincethe paper is not maintained under rigid tension while being dried but isfree to adjust itself to take a natural position under all conditions ofdrying and temperature changes, it is prevented from counter-curling andwrinkles are avoided.

In order that the paper will not be marked by continual contact with thecross members 11, throughout the drying operation, provision is made foradvancing the paper along the conveyer so that new portions of the papercontact with the cross members after a given interval of time. Eachcross member is provided with the sprocket wheel 30, which, whenrotated, serves to advance the cross member 11 to which it is connected.At spaced intervals along the travel of the conveyer, the pins 31 aresupported on the superstructure, or otherwise, so as to contact with theteeth of the sprocket wheels 30, so that as the conveyer moves, thesprocket wheels are rotated by contact with the pins 31. Figs. 2 and 3show the arrangement of the sprocket wheels 30 and the pins 31, withwhich they contact. While each cross member 11 is provided with asprocket wheel 30, the sprocket wheels are not shown on all of the crossmembers of Figs. 1 and 2, sufficient being shown, however, to illustratethe construction. With this arrangement, the sprocket wheels 30, and thecross members 11, with which they are associated, are rotated at spacedintervals along the travel of the conveyer, and, in rotating, they shiftthe paper along the conveyer, so that at each shift fresh surfaces ofthe paper contact with the cross members. The cross members, adapted tobe rotated, are provided with suitable bearings so that they may befreely rotated with the conveyer, as it moves through the dryingchamber, but since such arrangements are well known to those skilled inthe art, they will not be illustrated in detail.

Whereas one embodiment of the invention has been described for thepurpose of illustration, it should be understood that the invention isnot limited to the exact details described as many departures may bemade by those skilled in the art without departing from the spirit ofthe invention.

What I claim is:

Apparatus for the drying of moistened sheet material comprising a dryingchamber, an endless chain conveyer for carrying the material throughsaid chamber, means for feeding the material onto the upper side of saidconveyer, a roller for reversing the direction of movement of and forcausing the placing of the material onto the under side of saidconveyer, rotatable means for again reversing the direction of movementof said conveyer, and means for projecting airagainst said material tohold it against the conveyer during its travel around said rotatablemeans.

CHARLES C. WILLIS.

